private static void saveCrashInfo2File(String sb) {

    String fileName = "CSM.txt";
    FileWriter writer = null;
    try {
        File dir = new File("/sdcard/AAAAcsm/");
        if (!dir.exists())
            dir.mkdirs();
        //打开一个写文件器，构造函数中的第二个参数true表示以追加形式写文件
        writer = new FileWriter(new File(dir, fileName).getAbsolutePath(), true);
        writer.write(sb);
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (writer != null) {
            try {
                writer.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}

 

saveCrashInfo2File("Login:" + getEncryptCode() + "\n");